Perhaps the only thing keeping the paper business card from going the way of the typewriter in your real estate business is the social media address on it where clients can find you.

A growing number of companies are joining this online networking migration — it is estimated that more than 1.5 million businesses participate in social networks.

Weeding through the online assault of Facebook, Twitter, LinkedIn and other icons on websites can be frazzling, though, and a new industry of technology firms has emerged to offer tools and services that can help companies manage and organize their presence on those networks, and to capture people and profits.